Disadvantages: (1) The fastener (especially its screw) is easily lost;
(2) The members at the nodes are eccentrically connected, and the load and internal force are transmitted by the anti-sliding force, thus reducing their bearing capacity;
(3) The connection quality of fastener nodes is significantly affected by the quality of the fastener itself and the manipulation of workers.

2. Bowl button steel scaffolding
Adaptability: (1) Construct stereotyped scaffolding;
(2) Support frame for beam and slab frame (understand vertical load);
(3) Construct a mobile workbench;
Disadvantages: (1) There is no flexibility in the frame size, any change in the frame size must be replaced with another type of gantry and its accessories;
(2) The cross bracing is easy to break at the middle hinge point;
(3) The stereotyped scaffolding board is heavier;
(4) The price is more expensive;
Advantages: (1) The geometric dimensions of portal steel scaffolding are standardized.
(2) The structure is reasonable, the force bearing function is good, the strength of steel is fully utilized, and the bearing capacity is high.
(3) Easy to assemble and disassemble during construction, high erection efficiency, labor-saving, time-saving, safe, reliable, and economical.

3. Portal steel scaffolding

Adaptability: (1) Construction of various forms of scaffolding, formwork and other supports;
(2) Assemble the well frame;
(3) erecting ramps, sheds, stands and other temporary structures;
(4) As an aid to other types of scaffolding, strengthen the rods.